1. Field of the Invention
The present invention relates generally to a telecommunications system for providing a neutral metropolitan area tandem switch network independent of the incumbent local exchange carriers and, in particular, to a system that bypasses the incumbent local exchange carrier tandem switch by creating a higher level in the switching hierarchy above the current RBOC tandems with respect to switching carrier traffic between carriers and switching and transporting traffic between the carriers and the local exchange carrier (LEC) metropolitan central offices and the LEC Advanced Traffic Routing Services.
2. Description of the Prior Art
As the wireline and wireless telephone industry has evolved into a competitive market over the past two decades, one segment of the market has largely remained unchanged, namely, the manner in which traffic is routed into and out of a metropolitan region and between carriers serving those regions. In such cases, a LEC tandem network continues to be used. As will be explained below, this situation is a limitation to the continued expansion of the wireline and wireless telephone industry. An improved method and apparatus for routing such traffic is desired.
One segment of the wireline and wireless telephone industry that has had explosive growth since the divestiture of AT&T has been wireless carriers. Traditionally, the termination of calls to RBOC customers, depending on a call's duration and cost per minute, constitute upwards of 40% of the overall cost of the long distance call. In addition, the Telecommunications Act of 1996 allows the RBOCs to apply for entry into the long distance market. The FCC has granted some of these applications, and it is expected to grant significantly more shortly. Thus, the long distance carriers, like the CLECs and wireless carriers, now face the challenge of both competing with the RBOCs while paying fees for accessing their network.
With respect to wireline or wireless carriers providing local calling in a metropolitan area, these carriers traditionally interconnect their networks as well to the LEC network at the LEC tandems, as opposed to establishing connections to every central office served by the tandems, which can easily run between 20 and 50 central offices for each tandem in a metropolitan area. When terminating a local call to a RBOC local service customer, these competitive wireline and wireless carriers, similar to the long distance carriers, are charged tandem switching and transport between the LEC tandem and the terminating local central office. Depending on the LEC retail local calling plan, the rates for tandem switching and termination charged competitive carriers on a per call basis for terminating a call to a LEC local service customer can exceed the retail rate charged a LEC customer for making a similar call, thus making competing with the LEC extremely uneconomic. This vestige of the RBOCs' past legal monopoly makes it more difficult for competitive carriers by providing the RBOCs with a cross-subsidy that can be used to compete against the CLECs. While in theory the payment for terminating a call is reciprocal, because the RBOC started with nearly 100% market share, it will be years before the RBOC's face a material financial exposure for such terminating charges to be paid to CLECs, whereas CLECs view such charges as a barrier to entry and many have structured their networks and business plans in an attempt to minimize the impact of such fees. Moreover, to the extent a competitor is dependent on the LEC to be responsive in providing access to a portion of its network, that competitor risks its success. For example, there have been reports of the RBOCs not sufficiently growing their tandem networks to meet the capacity required by new competitive carriers. As a result, the competitors risk providing a deteriorating level of service (e.g., a high rate of busy signals) or incurring uneconomic network deployments to circumvent tandem bottlenecks and connect directly to high traffic RBOC central offices.
This dependence by competitive carriers on the RBOC tandem networks is exacerbated by the fact that not only are the competitors using the tandems to route traffic between the RBOC network and their networks, but also the RBOC tandems have become a point at which overlapping networks in a metropolitan area interconnect. Thus, the RBOC tandems by default have become the points at which competitors route traffic amongst themselves (transit traffic). Just as with traffic that terminates to customers of the RBOC, the RBOC is paid a fee by the competitive carriers for carrying this transit traffic even when an RBOC customer is not the called party. As a result, as competitors gain market share against the RBOC and exchange between themselves, the traffic really never leaves the tandem network; it continues to ride the RBOC network as transit traffic. These transit fees, of course, act to cross-subsidize the RBOC in its competition with these competitive networks. However, the RBOCs have little interest in supporting such traffic (i.e., traffic passing between two competitors) with capital improvements, prompt: customer service and order fulfillment. Indeed, the RBOCs have a disincentive to support such traffic, because deteriorating the quality of such transiting traffic could lead customers of a competitive carrier to return to the RBOCs as retail customers. The present alternative for competitive carriers seeking to exchange traffic between each other without going through the RBOC is for the competitive carriers to directly connect facilities between each other. Because of the varying amounts of traffic between such carriers as well as the traffic imbalance and the large and ever changing number of such carriers, this would be prohibitively uneconomic.
With its entrenched monopoly status, the RBOC are generally free to dictate the various technical interconnection requirements for metropolitan area networks needing to interconnect with the RBOC. These interconnection requirements, in addition to the fees charged for interconnection, increase substantially the costs for carriers to interconnect with the RBOC. Most challenging, the RBOC requires all carriers interconnecting with its network to do so on technical specifications dictated not by the advances in the market for technology, but by the legacy technical infrastructure of the RBOC circuit switch network. As a result, carriers with advanced, high capacity networks have to reduce their networks' efficiency each time they interconnect with the RBOC network. The following is an example of the types of costly, duplicative, and complex interconnection requirements facing a metropolitan CLEC needing to connect with the local RBOC to serve a metropolitan region. Wireless carriers and, to a lesser extent, long distance carriers (because they do not provide local calling, but only require interconnection for originating and terminating long distance calls) face a similar maze of complexity and cost when interconnecting with the RBOC:
As commonly prescribed by the interconnection requirements between RBOCs and CLECs, at least five (5) types of trunk groups must be planned, transported and terminated for each CLEC switch interconnected in an RBOC-served metropolitan area:                Trunk Group 1—Dedicated Local and dedicated IntraLATA Trunk Group(s) in Each Local Exchange Area        Trunk Group 2—InterLATA (Meet Point) Trunk Group routes to Access Tandem        Trunk Group 3—E911 Trunk Group to primary and redundant E911 Tandems        Trunk Group 4—High Volume Call In (HVCI)/Mass Calling (Choke) Trunk Group routes to HVCI Tandem        Trunk Group 5—Operator Services/Directory Assistance Trunk Group(s) routes to OS/DA Tandem        
As the following figures show, these trunking requirements rapidly become complex, redundant, and costly.
FIG. 1a Trunk Group 1a: A Single, Separate Local Tandem 10, Access Tandem 12. For each RBOC Local Tandem 10 in a metropolitan area, a separate transport facility must be connected to carry local calls originated in that local area for termination via switch 14 to RBOC customers in that local area. For each Access Tandem 12 in a metropolitan area, a separate transport facility must be established for IntraLATA calls originated in that LATA for termination via switch 14 to RBOC customers in that LATA.
FIG. 1b Trunk Group 1b: Combined Local and Access Tandems 16. In some situations, an RBOC may have a tandem switch functioning as a combined Local and Access Tandem 16. In those situations, a CLEC may combine local and IntraLATA traffic on the same transport facility to the combined Local and Access Tandem, but the CLEC must still (as described in FIG. 4 below) establish a separate transport facility just for Trunk Group 2, InterLATA traffic, even though it is terminating at the same combined Local and Access Tandem.
FIG. 2 Multiple Tandems 18 in a Metropolitan Area: Within each of these 5 trunk groups, additional separate trunks may be required based on growth and the number of tandems established by the RBOC. For example, in a large metropolitan area, such as the Chicago metropolitan area, there are currently eight combined Local and Access Tandems 18 in five separate locations, each serving specific Local Exchange Areas. As a result, a CLEC serving the Chicago metropolitan area must establish a Trunk Group 1b connection for each of the eight tandems 18 in the metropolitan area. Those skilled in the art should note that this is an example of the tandem interconnection required by Ameritech in Chicago LATA 357, and that the other LECs may require slightly different processes for the same purpose.
FIG. 3 RBOC Interconnection Rules Increase Cost: For Local Trunk Groups in each Local Exchange Area, the RBOC often establishes interconnection requirements that increase costs and complexity further, providing for example that:                Inter-Tandem switching is not allowed—i.e., a CLEC cannot pass traffic through one tandem to reach another tandem even in the event of overflow, but must have multiple dedicated tandem connections to each tandem.        Additional dedicated trunks can be required—for example, where traffic from a CLEC switch to specific RBOC Central Office or end office 20 reaches a quantity to support, in the RBOC's opinion, a dedicated facility between the CLEC and the RBOC the Central Office (e.g., 24 or more trunks) a dedicated local trunk group shall also be established by the CLEC to the RBOC End Office (EO) 20, thus causing the CLEC to incur additional port, transport and planning costs.        
FIG. 4 Trunk Group 2—InterLATA (Meet Point) Trunk Group 2: RBOCs require a separate facility=22 for traffic passing between a CLEC's customers and long distance carriers connected to the RBOCs' tandem networks. Again, many RBOC requirements increase the cost and complexity of these connections:                A dedicated InterLATA trunk group will be established for the transmission and routing of access traffic between CLEC's customers and long distance carriers sending or receiving long distance traffic from such customers via the RBOC Access Tandem 18.        When the RBOC has more than one Access Tandem 18 in a LATA, the CLEC must establish an InterLATA trunk group to each RBOC Access Tandem 18.        In no event will the RBOC route traffic through more than one Tandem 18 for connection to/from long distance carriers.        
FIG. 5 Trunk Group 3—E911 Trunk Group: To serve a metropolitan area, a CLEC often is required to connect to multiple E911 Trunk Groups.                A dedicated trunk group for each calling area shall be established to each appropriate E911 Tandem 24 within the local exchange area in which CLEC offers exchange service.        
FIG. 6 Trunk Group 4—High Volume Call In (HVCI)/Mass Calling (Choke) Trunk Group: To serve a metropolitan area, a CLEC is also required to establish:                A dedicated trunk group to the designated Public Response HVCI/Mass Calling Network Access Tandem 26 in each serving area        
FIG. 7 Trunk Group 5—Operator Services/Directory Assistance/Busy Line Verification/EI Trunk Group(s): To serve a metropolitan area, a CLEC is also required to establish a dedicated trunk groups to enable:                Busy Line Verification/Emergency Interrupt (BLV/EI)        Operator Assistance (0+, 0−)        Directory Assistance Call Completion (DACC)        Directory Assistance (DA)        
Thus, at a minimum, a CLEC launching service in the Chicago metropolitan area must establish at least 20 separate T-1 trunk groups to support interconnecting to Ameritech's 11 tandem switches 18, 24, 26, 28 in LATA 357.
FIG. 8 CLEC Costs Increase with Interconnection Complexity: FIG. 8 is an example of the cost incurred by the CLEC to arrange for such interconnections. The cost includes: switch port costs on the CLEC's switch 14, interconnection electronics 30, 31, 32 for the network transport, network planning costs, network transit costs to the interconnection points, multiplexing equipment 34, 36 at the Tandem Central Office, switch port costs on the Tandem switch and usage based switching fees charged by the RBOC to the CLEC. Because the RBOC limits the interconnection speeds to those compatible with its legacy circuit switches, CLECs incur unnecessary inefficiency in reducing their high bandwidth networks down to the T-1 and DS-3 levels of interconnection speed prescribed by the RBOCs.
As shown in FIG. 9, RBOC tandem interconnection trunking complexity increases exponentially in a region as both the type of public and private carrier networks increase (e.g., CLECs, wireless, cable television, long distance) and the absolute number of such carriers increase. As traffic between these carriers grows, RBOC policies and interconnection requirements continue to significantly increase planning complexity and costs while reducing network efficiency. For example, RBOC interconnection rules generally require that when transit traffic through a tandem (e.g. 38) from one CLEC to another CLEC or wireless carrier requires 24 or more trunks, the CLEC shall establish a direct trunk group between itself and the other CLEC or wireless carrier and not use the tandem 38 for traffic between such carriers. This requirement is similar to the requirement that a CLEC establish dedicated trunks to an end office when the CLEC's traffic terminating to the particular RBOC end office requires 24 or more trunks (see FIG. 3). Establishing such dedicated trunks adds additional costs for the competitive carriers by reducing switch port capacity, adding transport management and electronics, and reducing tandem trunking efficiency. As CLEC and wireless carriers grow and dedicated facilities are required among such carriers and between such carriers and the RBOC end offices, the fundamental premise of utilizing a switch to interconnect these overlapping carrier networks is destroyed, thus increasing cost for competitors. Without tandem switching, carriers would have to establish a mass of inefficient dedicated facilities as illustrated in FIG. 10. Above all, therefore, there exists a need to promote the development of a network alternative that breaks the cycle of relying on (and paying fees for) the RBOC network at the same time as competing with the RBOC. The more that neutral or independent network components are available to carriers competing with the RBOCs, the more that the forces of competition will develop in the telecommunications market. Such facilities can promote competition by being both competitor neutral—i.e., not establishing unreasonable rates or practices in an effort to deter competition—and technology neutral—i.e., not preferring a specific technology for anti-competitive reasons.
However, to date, no solution has been proposed which would enable a company independent of the RBOCs to provide critical functions of the local telephone network on a broad scale at a competitive cost. There is thus a great need in the art for a system and method which would enable a company independent of the RBOCs to provide cost competitive components of the local telephone network, and hence enable meaningful competition to the incumbent RBOCs in the local, wireless and long distance markets, without requiring a cost prohibitive infrastructure investment.
Accordingly, a LEC bypass technique is desired which promotes cost-effective competition with the LECs without requiring uneconomic significant infrastructure investment. Embodiments of the present invention have been designed to meet this great need in the art.
In addition to reducing the dependence by carriers on its competitor, the LEC, embodiments of the present invention have also been designed to meet another great need in the art, the need to significantly reduce the charges assessed by the LECs on most (i) long distance calls and (ii) local wireline (e.g., CLECs) and wireless (e.g., cellular) call terminations and the related traffic inefficiency, which cost consumers tens of billions of dollars each year.
Bypassing the LEC tandems and the associated inefficiencies could save the IXCs, CLECs and wireless carriers a significant portion of their service costs for providing telecommunications services and, once the associated savings are passed on to their subscribers, potentially save their customers billions of dollars each year. These cost savings from such LEC bypass will come in many forms. For example, the proprietor of the neutral tandem network (NTN) described below will be in a position to price their services dramatically different from the current RBOC interconnection pricing. Today, the RBOC's disparate, inefficient tandem connections covering discrete geographic areas require carriers to establish multiple connections to pass traffic across a given metropolitan area; each connection requiring separate monthly connection fees. The RBOCs also require carriers to separate traffic based on traffic types, e.g., local traffic versus long distance traffic. The proprietor of the NTN of the invention will enable carrier to terminate all such traffic using dramatically fewer connections, thus reducing carriers interconnection cost. Also, reducing interconnection points for terminating traffic will reduce the number of ports on carriers switches required to terminate such traffic, thus saving the carriers capital cost on their switches, which can be otherwise uses to create revenue producing services. Finally, carrier customers will find that they need fewer engineering resources for managing their interconnections because the NTN of the invention simplifies the establishment of such connections by essentially outsourcing the carrier interconnection process.
Even more critical for the development of competition in the telecommunications market is the addition of a neutral provider of this important portion of the network. The lack of readily available, affordable, scaleable local network assets is one of the primary obstacles to enhanced competition between the LECs and other potential entrants into the telecommunications marketplace.